Abstract: A cover cap (40) is provided for covering the open end of a support insulator (38) having a discharge electrode hanger rod (28) passing coaxially therethrough. The cover cap (40) comprises a top (42) and a sloping side wall (44) extending coaxially outwardly and downwardly from the perimeter edge (54) of the top (42) and having a radial lip (46) and an axial lip (48) extending outwardly at substantially right angles to each other from its lower perimeter surface. A tubular gas injection nozzle (92) having an elbow subtending an angle of 135 degrees, is provided in the sloping side wall (44) for passing a jet of scavenging gas into the interior region encompassed by the sloping side wall (44). At least one access opening (70) is provided in the sloping side wall for permitting access into the interior region encompassed by the sloping side wall (44).

Abstract: An electrostatic precipitator (10) having a casing (12) defining a precipitation chamber (6) wherein a plurality of discharge electrode frames (32) are disposed alternately between a plurality of collecting electrode plates (20). Each discharge electrode frame is comprised of a plurality of individual discharge electrode wires (36) tautly strung across a support frame. Individual discharge electrode wires are maintained in a taut condition during operation by tensioning coil springs (50) which interconnect neighboring discharge electrode wires to take-up any lengthening of the discharge electrode wires in a horizontal direction.